Accumulator for liquids under pressure



Filed Dec. 1, 1938 Patented Apr. 22, 1941 2,239,481 ACCUMULATOR FOBLIQUIDS UNDER PRESSURE All'redo Hiram Hunt Christensen, Buenos Alres,

Argentina Application December 1, 1938, Serlal No. 243,455 In ArgentinaMay 4, 1938 2 Claims.

The present invention relates to a novel accumulator for liquids underpressure, wherein use is made of compressed air as an elastic means tomaintain constant pressure.

For a better understanding of the invention the same is described in thefollowing specification taken in conjunction with the drawing in whichthe same reference characters denote similar or like parts. Fi 1 shows avertical medial section of the hydraulic accumulator according to theinvention.

Fig. 2 illustrates schematically. as an example,

complete equipment embodying the accumulator according to the invention.

The hydraulic accumulator which forms the object of this inventioncomprises a container, or receptacle, horizontally divided into twochambets 6 and 23 by means of an elastic diaphragm H.

The upper chamber 6 where the liquid under pressure accumulates is inconstant communication, by way of the holes 5 (Fig. 1) and a port I,with a general pressure line I (Fig. 2) of an installation in which areconnected the pump 26 and working apparatus such as a press 19.

The lower chamber 23 (Fig. 1) of the accumulator is in constantcommunication, by way of a channel 22, a space 2| and a port I9,with anairtight receptacle 24. This receptacle of adequate dimensions is filledwith air, or a gas, at a pressure equal to that to which the liquidaccumulated within the chamber 6 is to be subjected.

In this chamber 23 (Fig. 1) there is located a stem l3 slidable withinlimits corresponding to the height of the chamber its travelbeing'limited in an upward direction by a nut l6, and in a downwarddirection by a disc or plate I4. The said stem is urged towards itsupper position, as shown in the drawing, by a helical spring I5 arrangedwithin the stem and bearing against the bottomof a small air-tightchamber l8.

The purpose of providing this stem consists in actuating, at the extremepoints of its travel and with the aid of a slot, an electric switch 3|provided within the air-tight box 20 and the leadwires of which arebrought out through insulated bushings and connected to a 220 voltsupply line and to the motor 28 of the liquid injector pump 26 (Fig. 2).

The primary object of the disc M (Fig. 1) is to provide ample supportingsurface for the diaphragm I! and, further, in the extreme lower positionof thestem, to be interposed between the port 22 and the said diaphragmH so as to avoid the destruction of the diaphragm against the opening 22by action of the liquid under pressure, in the case that the apparatusshould become accidentally completely filled with liquid.

Similarly, within the upper chamber 6 is located a stem 8 terminating ina disc I and maintained in position by a spring 30 the travel of whichis limited by the said disc and the nut 9.

The sole object of this stem and disc is to cause the latter to beinterposed, in a manner similar to that described with reference to thedisc I and if by accident it should be required, between the port 5 andthe diaphragm ll, thus avoiding damage to the opening 6 by action of theair under pressure.

During operation, when liquid is drawn oil due to the functioning of thepress 26 (Fig. 2), or any other similar device the diaphragm ll (Fig. 1)is caused to move upwards actuated :by the air in chamber 23 and, as aconsequence, the stem II also rises until it reaches its upper limit andactuates the switch 3| closing the circuit to the motor which thenstarts operation of the pump.

When the pressure of the liquid forced into the line I by operation ofthe pump 26 rises above the pressure of the receptacle 24 liquid entersthe chamber 6 and the stem I3 is moved downwardly to open the switch inthe chamber 26 whereby the operation of the pump ceases.

As distinguished from accumulators provided with a piston andcounterweight, the accumulator according to the invention, shows theadvantage that, due to the use of a diaphragm which is substituted for apiston, and of the compressed air which is substituted for the usualcounterweight, I do away with the considerable variation in pressure dueto friction of the pistons and inertia of the counterweigh'ts, whichimpart abrupt blows to the system. Further, leakage is prevented sincethere are no packings nor stuffingboxes. The apparatus according to theinvention being light and of very small dimensions, the mounting thereofis extremely easy and simpie.

The present accumulator also lacks of the disadvantages of compressedair accumulators already known wherein the air is in direct contact withthe liquid, and as a result the air or gas becomes dissolved oremulsioned in part with the liquid, it being thus necessary'to'periodically supply air by means of a compressor, which causes theoperation to become complicated and costly. The accumulator according tothe inveuv tion also lacks the disadvantages inherent in compressed airaccumulators with piston free or separation between the liquid and theair. the .said piston creating friction and, further, it does not forman eflicient or perfect seal between both fluids, such as is the casewith a diaphragm.

What I claim is:

1. Apparatus for maintaining a uniform pressure in a fluid pressuresupply line comprising, a pump for forcing liquid into said line, amotor for driving said pump, a container, an elastic diaphragm dividingsaid container into two chambers, a pipe connecting said liquid supplyline with one of said chambers, a source of fluid pressure connectedwith the other chamber, a movable stem terminating in the last mentionedchamber adjacent said diaphragm, yieldable 2. In apparatus formaintaining a uniform pressure in a fluid pressure supply line, a. pumpfor forcing liquid into said line, a motor for driving said pump, acontainer, an elastic diaphragm dividing said container into twochambers, said container having a channel therein for admitting fluidpressure to one of said chambers, a stem arranged for sliding movementwithin said channel, said container having a port therein for admittingfluid from said supply line to the other of said chambers, a disccarried by said stem adapted to cover said channel when the diaphragm ismoved towards said channel,

yieldable means urging the disc of the stem into engagement with thediaphragm, a circuit for supplying current to said motor, and anelectric switch in said circuit actuated by movement of said stem foropening and closing said circuit.

ALFREDO HIRAM HUNT CHRISTENSEN.

